Plate heat exchanger in Germany by Alfa valve device to enter the Chinese market, although the time is not long, but in recent years, the plate heat exchanger in the domestic development rate is quite rapid. It is understood, plate heat exchanger used mainly in the large central air-conditioning, refrigerator or heat pump etc, at present the National Board for business is about forty to fifty, specializing in the production of plate for about thirty or so, Alfa Laval, Danfoss is the plate heat exchanger production enterprises in the typical.